n,[464] by Virginia against West Virginia to
determine the proportion of the public debt of the original State of
Virginia which the latter owed the former,[465] of one State against
another to enforce a contract between the two,[466] of a suit in equity
between States for the determination of a decedent's domicile for
inheritance tax purposes,[467] and of a suit by two States to restrain a
third from enforcing a natural gas measure which purported to restrict
the interstate flow of natural gas from the State in the event of a
shortage.[468] In general in taking jurisdiction of these suits, along
with those involving boundaries and the diversion or pollution of water
resources, the Supreme Court proceeded upon the liberal construction of
the term "controversies between two or more States" enunciated in Rhode
Island _v._ Massachusetts,[469] and fortified by Chief Justice
Marshall's dictum in Cohens _v._ Virginia[470] concerning jurisdiction
because of the parties to a case, that "it is entirely unimportant, what
may be the subject of controversy. Be it what it may, these parties have
a constitutional right to come into the Courts of the Union."

CASES OF WHICH THE COURT HAS DECLINED JURISDICTION

In other cases, however, the Court, centering its attention upon the
elements of a case or controversy, has declined jurisdiction. Thus in
Alabama _v._ Arizona[471] where Alabama sought to enjoin 19 States from
regulating or prohibiting the sale of convict-made goods, the Court went
far beyond holding that it had no jurisdiction, and indicated that
jurisdiction of suits between States will be exercised only when
absolutely necessary, that the equity requirements in a suit between
States are more exacting than in a suit between private persons, that
the threatened injury to a plaintiff State must be of great magnitude
and imminent, and that the burden on the plaintiff State to establish
all the elements of a case is greater than that generally required by a
petitioner seeking an injunction suit in cases between private parties.

Pursuing a similar line of reasoning, the Court declined to take
jurisdiction of a suit brought by Massachusetts against Missouri and
certain of its citizens to prevent Missouri from levying inheritance
taxes upon intangibles held in trust in Missouri by resident trustees.
In holding that the complaint presented no justiciable controversy, the
Court declared that to constitute such a controversy, the c